/*
 * Licensed to the OpenAirInterface (OAI) Software Alliance under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The OpenAirInterface Software Alliance licenses this file to You under
 * the OAI Public License, Version 1.1  (the "License"); you may not use this file
 * except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.openairinterface.org/?page_id=698
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 *-------------------------------------------------------------------------------
 * For more information about the OpenAirInterface (OAI) Software Alliance:
 *      contact@openairinterface.org
 */

/*! \file m3ap_MME.c
 * \brief m3ap tasks for MME
 * \author Javier Morgade  <javier.morgade@ieee.org>
 * \date 2019
 * \version 0.1
 */

#include <pthread.h>
#include <stdio.h>
#include <stdlib.h>
#include <stdint.h>
#include <arpa/inet.h>

#include "intertask_interface.h"

#include "m3ap_MME.h"
#include "m3ap_MME_defs.h"
#include "m3ap_MME_management_procedures.h"
#include "m3ap_MME_handler.h"
//#include "m3ap_MME_generate_messages.h"
#include "m3ap_common.h"
#include "m3ap_MME_interface_management.h"
#include "m3ap_ids.h"
#include "m3ap_timers.h"

#include "queue.h"
#include "assertions.h"
#include "conversions.h"

struct m3ap_mme_map;
struct m3ap_MME_data_s;

m3ap_setup_req_t *m3ap_mme_data_from_mce;

RB_PROTOTYPE(m3ap_mme_map, m3ap_MME_data_s, entry, m3ap_MME_compare_assoc_id);

static
void m3ap_MME_handle_sctp_data_ind(instance_t instance, sctp_data_ind_t *sctp_data_ind);

static
void m3ap_MME_handle_sctp_association_resp(instance_t instance, sctp_new_association_resp_t *sctp_new_association_resp);

static
void m3ap_MME_handle_sctp_association_ind(instance_t instance, sctp_new_association_ind_t *sctp_new_association_ind);

//static
//void m3ap_MME_handle_register_MME(instance_t instance,
//                                  m3ap_register_mce_req_t *m3ap_register_MME);
static
void m3ap_MME_register_MME(m3ap_MME_instance_t *instance_p,
                           net_ip_address_t    *target_MME_ip_addr,
                           net_ip_address_t    *local_ip_addr,
                           uint16_t             in_streams,
                           uint16_t             out_streams,
                           uint32_t             mme_port_for_M3C,
                           int                  multi_sd);

//static
//void m3ap_MME_handle_handover_req(instance_t instance,
//                                  m3ap_handover_req_t *m3ap_handover_req);
//
//static
//void m3ap_MME_handle_handover_req_ack(instance_t instance,
//                                      m3ap_handover_req_ack_t *m3ap_handover_req_ack);
//
//static
//void m3ap_MME_ue_context_release(instance_t instance,
//                                 m3ap_ue_context_release_t *m3ap_ue_context_release);
//

static
void m3ap_MME_handle_sctp_data_ind(instance_t instance, sctp_data_ind_t *sctp_data_ind) {
  int result;
  DevAssert(sctp_data_ind != NULL);
  m3ap_MME_handle_message(instance, sctp_data_ind->assoc_id, sctp_data_ind->stream,
                          sctp_data_ind->buffer, sctp_data_ind->buffer_length);
  result = itti_free(TASK_UNKNOWN, sctp_data_ind->buffer);
  AssertFatal (result == EXIT_SUCCESS, "Failed to free memory (%d)!\n", result);
}

static
void m3ap_MME_handle_sctp_association_resp(instance_t instance, sctp_new_association_resp_t *sctp_new_association_resp) {

   DevAssert(sctp_new_association_resp != NULL);

  if (sctp_new_association_resp->sctp_state != SCTP_STATE_ESTABLISHED) {
    LOG_W(M3AP, "Received unsuccessful result for SCTP association (%u), instance %d, cnx_id %u\n",
              sctp_new_association_resp->sctp_state,
              instance,
              sctp_new_association_resp->ulp_cnx_id);

    if (sctp_new_association_resp->sctp_state == SCTP_STATE_SHUTDOWN)
      //proto_agent_stop(instance);
      //f1ap_handle_setup_message(instance, sctp_new_association_resp->sctp_state == SCTP_STATE_SHUTDOWN);
    return; // exit -1 for debugging
  }

   // go to an init func
  m3ap_mme_data_from_mce = (m3ap_setup_req_t *)calloc(1, sizeof(m3ap_setup_req_t));
  // save the assoc id
  m3ap_mme_data_from_mce->assoc_id         = sctp_new_association_resp->assoc_id;
  m3ap_mme_data_from_mce->sctp_in_streams  = sctp_new_association_resp->in_streams;
  m3ap_mme_data_from_mce->sctp_out_streams = sctp_new_association_resp->out_streams;



 // m3ap_MME_instance_t *instance_p;
 // m3ap_MME_data_t *m3ap_mme_data_p;
 // DevAssert(sctp_new_association_resp != NULL);
 // printf("m3ap_MME_handle_sctp_association_resp at 1\n");
 // dump_mme_trees_m3();
 // instance_p = instance;//m3ap_MME_get_instance(instance);
 // DevAssert(instance_p != NULL);

 // /* if the assoc_id is already known, it is certainly because an IND was received
 //  * before. In this case, just update streams and return
 //  */
 // if (sctp_new_association_resp->assoc_id != -1) {
 //   m3ap_mme_data_p = m3ap_get_MME(instance_p, sctp_new_association_resp->assoc_id,
 //                                  sctp_new_association_resp->ulp_cnx_id);

 //   if (m3ap_mme_data_p != NULL) {
 //     /* some sanity check - to be refined at some point */
 //     if (sctp_new_association_resp->sctp_state != SCTP_STATE_ESTABLISHED) {
 //       M3AP_ERROR("m3ap_mme_data_p not NULL and sctp state not SCTP_STATE_ESTABLISHED, what to do?\n");
 //       abort();
 //     }

 //     m3ap_mme_data_p->in_streams  = sctp_new_association_resp->in_streams;
 //     m3ap_mme_data_p->out_streams = sctp_new_association_resp->out_streams;
 //     return;
 //   }
 // }

 // m3ap_mme_data_p = m3ap_get_MME(instance_p, -1,
 //                                sctp_new_association_resp->ulp_cnx_id);
 // DevAssert(m3ap_mme_data_p != NULL);
 // printf("m3ap_MME_handle_sctp_association_resp at 2\n");
 // dump_mme_trees_m3();

 // if (sctp_new_association_resp->sctp_state != SCTP_STATE_ESTABLISHED) {
 //   M3AP_WARN("Received unsuccessful result for SCTP association (%u), instance %d, cnx_id %u\n",
 //             sctp_new_association_resp->sctp_state,
 //             instance,
 //             sctp_new_association_resp->ulp_cnx_id);
 //   //m3ap_eNB_handle_m3_setup_message(instance_p, m3ap_mme_data_p,
 //                                //sctp_new_association_resp->sctp_state == SCTP_STATE_SHUTDOWN);
 //   return;
 // }

 // printf("m3ap_MME_handle_sctp_association_resp at 3\n");
 // dump_mme_trees_m3();
 // /* Update parameters */
 // m3ap_mme_data_p->assoc_id    = sctp_new_association_resp->assoc_id;
 // m3ap_mme_data_p->in_streams  = sctp_new_association_resp->in_streams;
 // m3ap_mme_data_p->out_streams = sctp_new_association_resp->out_streams;
 // printf("m3ap_MME_handle_sctp_association_resp at 4\n");
 // dump_mme_trees_m3();
 // /* Prepare new m3 Setup Request */
 // //m3ap_MME_generate_m3_setup_request(instance_p, m3ap_mme_data_p);
}

static
void m3ap_MME_handle_sctp_association_ind(instance_t instance, sctp_new_association_ind_t *sctp_new_association_ind) {
  //m3ap_MME_instance_t *instance_p;
  //m3ap_MME_data_t *m3ap_mme_data_p;
  //printf("m3ap_MME_handle_sctp_association_ind at 1 (called for instance %d)\n", instance);
  ///dump_mme_trees_m3();
  ///DevAssert(sctp_new_association_ind != NULL);
  ///instance_p = instance;//m3ap_MME_get_instance(instance);
  ///DevAssert(instance_p != NULL);
  ///m3ap_mme_data_p = m3ap_get_MME(instance_p, sctp_new_association_ind->assoc_id, -1);

  ///if (m3ap_mme_data_p != NULL) abort();

  /////  DevAssert(m3ap_enb_data_p != NULL);
  ///if (m3ap_mme_data_p == NULL) {
  ///  /* Create new MME descriptor */
  ///  m3ap_mme_data_p = calloc(1, sizeof(*m3ap_mme_data_p));
  ///  DevAssert(m3ap_mme_data_p != NULL);
  ///  m3ap_mme_data_p->cnx_id                = m3ap_MME_fetch_add_global_cnx_id();
  ///  m3ap_mme_data_p->m3ap_MME_instance = instance_p;
  ///  /* Insert the new descriptor in list of known MME
  ///   * but not yet associated.
  ///   */
  ///  RB_INSERT(m3ap_mme_map, &instance_p->m3ap_mme_head, m3ap_mme_data_p);
  ///  m3ap_mme_data_p->state = M3AP_MME_STATE_CONNECTED;
  ///  instance_p->m3_target_mme_nb++;

  ///  if (instance_p->m3_target_mme_pending_nb > 0) {
  ///    instance_p->m3_target_mme_pending_nb--;
  ///  }
  ///} else {
  ///  M3AP_WARN("m3ap_mme_data_p already exists\n");
  ///}

  ///printf("m3ap_MME_handle_sctp_association_ind at 2\n");
  ///dump_mme_trees_m3();
  ////* Update parameters */
  ///m3ap_mme_data_p->assoc_id    = sctp_new_association_ind->assoc_id;
  ///m3ap_mme_data_p->in_streams  = sctp_new_association_ind->in_streams;
  ///m3ap_mme_data_p->out_streams = sctp_new_association_ind->out_streams;
  ///printf("m3ap_MME_handle_sctp_association_ind at 3\n");
  ///dump_mme_trees_m3();
}

int m3ap_MME_init_sctp (m3ap_MME_instance_t *instance_p,
                        net_ip_address_t    *local_ip_addr,
                        uint32_t mme_port_for_M3C) {
  // Create and alloc new message
  MessageDef                             *message;
  sctp_init_t                            *sctp_init  = NULL;
  DevAssert(instance_p != NULL);
  DevAssert(local_ip_addr != NULL);
  message = itti_alloc_new_message (TASK_M3AP_MME, SCTP_INIT_MSG_MULTI_REQ);
  sctp_init = &message->ittiMsg.sctp_init_multi;
  sctp_init->port = mme_port_for_M3C;
  sctp_init->ppid = M3AP_SCTP_PPID;
  sctp_init->ipv4 = 1;
  sctp_init->ipv6 = 0;
  sctp_init->nb_ipv4_addr = 1;
#if 0
  memcpy(&sctp_init->ipv4_address,
         local_ip_addr,
         sizeof(*local_ip_addr));
#endif
  sctp_init->ipv4_address[0] = inet_addr(local_ip_addr->ipv4_address);
  /*
   * SR WARNING: ipv6 multi-homing fails sometimes for localhost.
   * * * * Disable it for now.
   */
  sctp_init->nb_ipv6_addr = 0;
  sctp_init->ipv6_address[0] = "0:0:0:0:0:0:0:1";
  return itti_send_msg_to_task (TASK_SCTP, instance_p->instance, message);
}

static void m3ap_MME_register_MME(m3ap_MME_instance_t *instance_p,
                                  net_ip_address_t    *target_MME_ip_address,
                                  net_ip_address_t    *local_ip_addr,
                                  uint16_t             in_streams,
                                  uint16_t             out_streams,
                                  uint32_t             mme_port_for_M3C,
                                  int                  multi_sd) {
 // MessageDef                       *message                   = NULL;
 // sctp_new_association_req_multi_t *sctp_new_association_req  = NULL;
 // m3ap_MME_data_t                  *m3ap_mme_data             = NULL;
 // DevAssert(instance_p != NULL);
 // DevAssert(target_MME_ip_address != NULL);
 // message = itti_alloc_new_message(TASK_M3AP_MME, SCTP_NEW_ASSOCIATION_REQ_MULTI);
 // sctp_new_association_req = &message->ittiMsg.sctp_new_association_req_multi;
 // sctp_new_association_req->port = mme_port_for_M3C;
 // sctp_new_association_req->ppid = M3AP_SCTP_PPID;
 // sctp_new_association_req->in_streams  = in_streams;
 // sctp_new_association_req->out_streams = out_streams;
 // sctp_new_association_req->multi_sd = multi_sd;
 // memcpy(&sctp_new_association_req->remote_address,
 //        target_MME_ip_address,
 //        sizeof(*target_MME_ip_address));
 // memcpy(&sctp_new_association_req->local_address,
 //        local_ip_addr,
 //        sizeof(*local_ip_addr));
 // /* Create new MME descriptor */
 // m3ap_mme_data = calloc(1, sizeof(*m3ap_mme_data));
 // DevAssert(m3ap_mme_data != NULL);
 // m3ap_mme_data->cnx_id                = m3ap_MME_fetch_add_global_cnx_id();
 // sctp_new_association_req->ulp_cnx_id = m3ap_mme_data->cnx_id;
 // m3ap_mme_data->assoc_id          = -1;
 // m3ap_mme_data->m3ap_MME_instance = instance_p;
 // /* Insert the new descriptor in list of known MME
 //  * but not yet associated.
 //  */
 // RB_INSERT(m3ap_mme_map, &instance_p->m3ap_mme_head, m3ap_mme_data);
 // m3ap_mme_data->state = M3AP_MME_STATE_WAITING;
 // instance_p->m3_target_mme_nb ++;
 // instance_p->m3_target_mme_pending_nb ++;
 // itti_send_msg_to_task(TASK_SCTP, instance_p->instance, message);
}

//static
//void m3ap_MME_handle_register_MME(instance_t instance,
//                                  m3ap_register_mce_req_t *m3ap_register_MME) {
//  m3ap_MME_instance_t *new_instance;
//  DevAssert(m3ap_register_MME != NULL);
//  /* Look if the provided instance already exists */
//  new_instance = m3ap_MME_get_instance(instance);
//
//  if (new_instance != NULL) {
//    /* Checks if it is a retry on the same MME */
//    DevCheck(new_instance->MME_id == m3ap_register_MME->MME_id, new_instance->MME_id, m3ap_register_MME->MME_id, 0);
//    DevCheck(new_instance->cell_type == m3ap_register_MME->cell_type, new_instance->cell_type, m3ap_register_MME->cell_type, 0);
//    DevCheck(new_instance->tac == m3ap_register_MME->tac, new_instance->tac, m3ap_register_MME->tac, 0);
//    DevCheck(new_instance->mcc == m3ap_register_MME->mcc, new_instance->mcc, m3ap_register_MME->mcc, 0);
//    DevCheck(new_instance->mnc == m3ap_register_MME->mnc, new_instance->mnc, m3ap_register_MME->mnc, 0);
//    M3AP_WARN("MME[%d] already registered\n", instance);
//  } else {
//    new_instance = calloc(1, sizeof(m3ap_MME_instance_t));
//    DevAssert(new_instance != NULL);
//    RB_INIT(&new_instance->m3ap_mme_head);
//    /* Copy usefull parameters */
//    new_instance->instance         = instance;
//    new_instance->MME_name         = m3ap_register_MME->MME_name;
//    new_instance->MME_id           = m3ap_register_MME->MME_id;
//    new_instance->cell_type        = m3ap_register_MME->cell_type;
//    new_instance->tac              = m3ap_register_MME->tac;
//    new_instance->mcc              = m3ap_register_MME->mcc;
//    new_instance->mnc              = m3ap_register_MME->mnc;
//    new_instance->mnc_digit_length = m3ap_register_MME->mnc_digit_length;
//    new_instance->num_cc           = m3ap_register_MME->num_cc;
//
//    m3ap_id_manager_init(&new_instance->id_manager);
//    m3ap_timers_init(&new_instance->timers,
//                     m3ap_register_MME->t_reloc_prep,
//                     m3ap_register_MME->tm3_reloc_overall);
//
//    for (int i = 0; i< m3ap_register_MME->num_cc; i++) {
//      new_instance->eutra_band[i]              = m3ap_register_MME->eutra_band[i];
//      new_instance->downlink_frequency[i]      = m3ap_register_MME->downlink_frequency[i];
//      new_instance->uplink_frequency_offset[i] = m3ap_register_MME->uplink_frequency_offset[i];
//      new_instance->Nid_cell[i]                = m3ap_register_MME->Nid_cell[i];
//      new_instance->N_RB_DL[i]                 = m3ap_register_MME->N_RB_DL[i];
//      new_instance->frame_type[i]              = m3ap_register_MME->frame_type[i];
//      new_instance->fdd_earfcn_DL[i]           = m3ap_register_MME->fdd_earfcn_DL[i];
//      new_instance->fdd_earfcn_UL[i]           = m3ap_register_MME->fdd_earfcn_UL[i];
//    }
//
//    DevCheck(m3ap_register_MME->nb_m3 <= M3AP_MAX_NB_MME_IP_ADDRESS,
//             M3AP_MAX_NB_MME_IP_ADDRESS, m3ap_register_MME->nb_m3, 0);
//    memcpy(new_instance->target_mme_m3_ip_address,
//           m3ap_register_MME->target_mme_m3_ip_address,
//           m3ap_register_MME->nb_m3 * sizeof(net_ip_address_t));
//    new_instance->nb_m3             = m3ap_register_MME->nb_m3;
//    new_instance->mme_m3_ip_address = m3ap_register_MME->mme_m3_ip_address;
//    new_instance->sctp_in_streams   = m3ap_register_MME->sctp_in_streams;
//    new_instance->sctp_out_streams  = m3ap_register_MME->sctp_out_streams;
//    new_instance->mme_port_for_M3C  = m3ap_register_MME->mme_port_for_M3C;
//    /* Add the new instance to the list of MME (meaningfull in virtual mode) */
//    m3ap_MME_insert_new_instance(new_instance);
//    M3AP_INFO("Registered new MME[%d] and %s MME id %u\n",
//              instance,
//              m3ap_register_MME->cell_type == CELL_MACRO_ENB ? "macro" : "home",
//              m3ap_register_MME->MME_id);
//
//    /* initiate the SCTP listener */
//    if (m3ap_MME_init_sctp(new_instance,&m3ap_register_MME->mme_m3_ip_address,m3ap_register_MME->mme_port_for_M3C) <  0 ) {
//      M3AP_ERROR ("Error while sending SCTP_INIT_MSG to SCTP \n");
//      return;
//    }
//
//    M3AP_INFO("MME[%d] MME id %u acting as a listner (server)\n",
//              instance, m3ap_register_MME->MME_id);
//  }
//}

static
void m3ap_MME_handle_sctp_init_msg_multi_cnf(
  instance_t instance_id,
  sctp_init_msg_multi_cnf_t *m) {
  m3ap_MME_instance_t *instance;
  int index;
  DevAssert(m != NULL);
  instance = m3ap_MME_get_instance(instance_id);
  DevAssert(instance != NULL);
  instance->multi_sd = m->multi_sd;

  /* Exit if CNF message reports failure.
   * Failure means multi_sd < 0.
   */
  if (instance->multi_sd < 0) {
    M3AP_ERROR("Error: be sure to properly configure M2 in your configuration file.\n");
    DevAssert(instance->multi_sd >= 0);
  }

  /* Trying to connect to the provided list of MME ip address */

  for (index = 0; index < instance->nb_m3; index++) {
    M3AP_INFO("MME[%d] MME id %u acting as an initiator (client)\n",
              instance_id, instance->MME_id);
    m3ap_MME_register_MME(instance,
                          &instance->target_mme_m3_ip_address[index],
                          &instance->mme_m3_ip_address,
                          instance->sctp_in_streams,
                          instance->sctp_out_streams,
                          instance->mme_port_for_M3C,
                          instance->multi_sd);
  }
}

//static
//void m3ap_MME_handle_handover_req(instance_t instance,
//                                  m3ap_handover_req_t *m3ap_handover_req)
//{
//  m3ap_MME_instance_t *instance_p;
//  m3ap_MME_data_t     *target;
//  m3ap_id_manager     *id_manager;
//  int                 ue_id;
//
//  int target_pci = m3ap_handover_req->target_physCellId;
//
//  instance_p = m3ap_MME_get_instance(instance);
//  DevAssert(instance_p != NULL);
//
//  target = m3ap_is_MME_pci_in_list(target_pci);
//  DevAssert(target != NULL);
//
//  /* allocate m3ap ID */
//  id_manager = &instance_p->id_manager;
//  ue_id = m3ap_allocate_new_id(id_manager);
//  if (ue_id == -1) {
//    M3AP_ERROR("could not allocate a new M3AP UE ID\n");
//    /* TODO: cancel handover: send (to be defined) message to RRC */
//    exit(1);
//  }
//  /* id_source is ue_id, id_target is unknown yet */
//  m3ap_set_ids(id_manager, ue_id, m3ap_handover_req->rnti, ue_id, -1);
//  m3ap_id_set_state(id_manager, ue_id, M2ID_STATE_SOURCE_PREPARE);
//  m3ap_set_reloc_prep_timer(id_manager, ue_id,
//                            m3ap_timer_get_tti(&instance_p->timers));
//  m3ap_id_set_target(id_manager, ue_id, target);
//
//  m3ap_MME_generate_m3_handover_request(instance_p, target, m3ap_handover_req, ue_id);
//}

//static
//void m3ap_MME_handle_handover_req_ack(instance_t instance,
//                                      m3ap_handover_req_ack_t *m3ap_handover_req_ack)
//{
//  /* TODO: remove this hack (the goal is to find the correct
//   * eNodeB structure for the other end) - we need a proper way for RRC
//   * and M3AP to identify eNodeBs
//   * RRC knows about mod_id and M3AP knows about MME_id (MME_ID in
//   * the configuration file)
//   * as far as I understand.. CROUX
//   */
//  m3ap_MME_instance_t *instance_p;
//  m3ap_MME_data_t     *target;
//  int source_assoc_id = m3ap_handover_req_ack->source_assoc_id;
//  int                 ue_id;
//  int                 id_source;
//  int                 id_target;
//
//  instance_p = m3ap_MME_get_instance(instance);
//  DevAssert(instance_p != NULL);
//
//  target = m3ap_get_MME(NULL, source_assoc_id, 0);
//  DevAssert(target != NULL);
//
//  /* rnti is a new information, save it */
//  ue_id     = m3ap_handover_req_ack->m3_id_target;
//  id_source = m3ap_id_get_id_source(&instance_p->id_manager, ue_id);
//  id_target = ue_id;
//  m3ap_set_ids(&instance_p->id_manager, ue_id, m3ap_handover_req_ack->rnti, id_source, id_target);
//
//  m3ap_MME_generate_m3_handover_request_ack(instance_p, target, m3ap_handover_req_ack);
//}
//
//static
//void m3ap_MME_ue_context_release(instance_t instance,
//                                 m3ap_ue_context_release_t *m3ap_ue_context_release)
//{
//  m3ap_MME_instance_t *instance_p;
//  m3ap_MME_data_t     *target;
//  int source_assoc_id = m3ap_ue_context_release->source_assoc_id;
//  int ue_id;
//  instance_p = m3ap_MME_get_instance(instance);
//  DevAssert(instance_p != NULL);
//
//  target = m3ap_get_MME(NULL, source_assoc_id, 0);
//  DevAssert(target != NULL);
//
//  m3ap_MME_generate_m3_ue_context_release(instance_p, target, m3ap_ue_context_release);
//
//  /* free the M3AP UE ID */
//  ue_id = m3ap_find_id_from_rnti(&instance_p->id_manager, m3ap_ue_context_release->rnti);
//  if (ue_id == -1) {
//    M3AP_ERROR("could not find UE %x\n", m3ap_ue_context_release->rnti);
//    exit(1);
//  }
//  m3ap_release_id(&instance_p->id_manager, ue_id);
//}

void MME_task_send_sctp_init_req(instance_t enb_id, m3ap_mme_sctp_req_t * m3ap_mme_sctp_req) {
  // 1. get the itti msg, and retrive the enb_id from the message
  // 2. use RC.rrc[enb_id] to fill the sctp_init_t with the ip, port
  // 3. creat an itti message to init

  MessageDef  *message_p = NULL;

  message_p = itti_alloc_new_message (TASK_M3AP_MME, SCTP_INIT_MSG);
if(m3ap_mme_sctp_req==NULL) {
  LOG_I(M3AP, "M3AP_SCTP_REQ(create socket)\n");
  message_p->ittiMsg.sctp_init.port = M3AP_PORT_NUMBER;
  message_p->ittiMsg.sctp_init.ppid = M3AP_SCTP_PPID;
  message_p->ittiMsg.sctp_init.ipv4 = 1;
  message_p->ittiMsg.sctp_init.ipv6 = 0;
  message_p->ittiMsg.sctp_init.nb_ipv4_addr = 1;
  //message_p->ittiMsg.sctp_init.ipv4_address[0] = inet_addr(RC.rrc[enb_id]->eth_params_s.my_addr);
  message_p->ittiMsg.sctp_init.ipv4_address[0] = inet_addr("127.0.0.8");

}else{

  LOG_I(M3AP, "M3AP_SCTP_REQ(create socket) %s\n",m3ap_mme_sctp_req->mme_m3_ip_address.ipv4_address);
 message_p->ittiMsg.sctp_init.port = m3ap_mme_sctp_req->mme_port_for_M3C;
  message_p->ittiMsg.sctp_init.ppid = M3AP_SCTP_PPID;
  message_p->ittiMsg.sctp_init.ipv4 = 1;
  message_p->ittiMsg.sctp_init.ipv6 = 0;
  message_p->ittiMsg.sctp_init.nb_ipv4_addr = 1;
  //message_p->ittiMsg.sctp_init.ipv4_address[0] = inet_addr(RC.rrc[enb_id]->eth_params_s.my_addr);
  message_p->ittiMsg.sctp_init.ipv4_address[0] = inet_addr(m3ap_mme_sctp_req->mme_m3_ip_address.ipv4_address);
 } 

  /*
   * SR WARNING: ipv6 multi-homing fails sometimes for localhost.
   * * * * Disable it for now.
   */
  message_p->ittiMsg.sctp_init.nb_ipv6_addr = 0;
  message_p->ittiMsg.sctp_init.ipv6_address[0] = "0:0:0:0:0:0:0:1";

  itti_send_msg_to_task(TASK_SCTP, enb_id, message_p);
}

void *m3ap_MME_task(void *arg) {
  MessageDef *received_msg = NULL;
  int         result;
  M3AP_DEBUG("Starting M3AP layer\n");
  m3ap_MME_prepare_internal_data();
  itti_mark_task_ready(TASK_M3AP_MME);

  //MME_task_send_sctp_init_req(0,NULL);


  while (1) {
    itti_receive_msg(TASK_M3AP_MME, &received_msg);

    switch (ITTI_MSG_ID(received_msg)) {
      case MESSAGE_TEST:
	LOG_W(M3AP,"MME Received MESSAGE_TEST Message\n");
	//MessageDef * message_p = itti_alloc_new_message(TASK_M3AP_MME, MESSAGE_TEST);
        //itti_send_msg_to_task(TASK_M3AP, 1/*ctxt_pP->module_id*/, message_p);
	break;
      case TERMINATE_MESSAGE:
        M3AP_WARN(" *** Exiting M3AP thread\n");
        itti_exit_task();
        break;

//      case M3AP_SUBFRAME_PROCESS:
//        m3ap_check_timers(ITTI_MESSAGE_GET_INSTANCE(received_msg));
//        break;
//
//      case M3AP_REGISTER_MME_REQ:
//	LOG_W(M3AP,"MME Received M3AP_REGISTER_MME_REQ Message\n");
//        m3ap_MME_handle_register_MME(ITTI_MESSAGE_GET_INSTANCE(received_msg),
//                                     &M3AP_REGISTER_MME_REQ(received_msg));
//        break;
//

      case M3AP_MME_SCTP_REQ:
  	MME_task_send_sctp_init_req(ITTI_MESSAGE_GET_INSTANCE(received_msg),
				    &M3AP_MME_SCTP_REQ(received_msg));
	break;

      case M3AP_SETUP_RESP:
	LOG_I(M3AP,"MME Received M3AP_SETUP_RESP Message\n");
	MME_send_M3_SETUP_RESPONSE(ITTI_MESSAGE_GET_INSTANCE(received_msg),
				    &M3AP_SETUP_RESP(received_msg));
	break;
//	break;
//
//      case M3AP_SETUP_FAILURE:
//	LOG_W(M3AP,"MME Received M3AP_SETUP_FAILURE Message\n");
//	MME_send_M2_SETUP_FAILURE(ITTI_MESSAGE_GET_INSTANCE(received_msg),
//				    &M3AP_SETUP_FAILURE(received_msg));
//	break;
//
//      case M3AP_MBMS_SCHEDULING_INFORMATION:
//	LOG_W(M3AP,"MME Received M3AP_MBMS_SCHEDULING_INFORMATION Message\n");
//        MME_send_MBMS_SCHEDULING_INFORMATION(0,
//						&M3AP_MBMS_SCHEDULING_INFORMATION(received_msg));
//
       case M3AP_MBMS_SESSION_START_REQ:
	LOG_I(M3AP,"MME Received M3AP_MBMS_SESSION_START_REQ Message\n");
        MME_send_MBMS_SESSION_START_REQUEST(ITTI_MESSAGE_GET_INSTANCE(received_msg),
						&M3AP_MBMS_SESSION_START_REQ(received_msg));
	break;
//
       case M3AP_MBMS_SESSION_STOP_REQ:
	LOG_I(M3AP,"MME Received M3AP_MBMS_SESSION_STOP_REQ Message\n");
        MME_send_MBMS_SESSION_STOP_REQUEST(ITTI_MESSAGE_GET_INSTANCE(received_msg),
						&M3AP_MBMS_SESSION_STOP_REQ(received_msg));
	break;
//	
       case M3AP_MBMS_SESSION_UPDATE_REQ:
	LOG_I(M3AP,"MME Received M3AP_MBMS_SESSION_UPDATE_REQ Message\n");
       // MME_send_MBMS_SESSION_UPDATE_REQUEST(ITTI_MESSAGE_GET_INSTANCE(received_msg),
	//					&M3AP_MBMS_SESSION_UPDATE_REQ(received_msg));
	break;
//
//       case M3AP_RESET:
//	LOG_W(M3AP,"MME Received M3AP_RESET Message\n");
//        MME_send_RESET(ITTI_MESSAGE_GET_INSTANCE(received_msg),
//						&M3AP_RESET(received_msg));
//	break;
//
//       case M3AP_ENB_CONFIGURATION_UPDATE_ACK:
//	LOG_W(M3AP,"MME Received M3AP_ENB_CONFIGURATION_UPDATE_ACK Message\n");
//        MME_send_ENB_CONFIGURATION_UPDATE_ACKNOWLEDGE(ITTI_MESSAGE_GET_INSTANCE(received_msg),
//						&M3AP_ENB_CONFIGURATION_UPDATE_ACK(received_msg));
//	break;
//
//       case M3AP_ENB_CONFIGURATION_UPDATE_FAILURE:
//	LOG_W(M3AP,"MME Received M3AP_ENB_CONFIGURATION_UPDATE_FAILURE Message\n");
//        MME_send_ENB_CONFIGURATION_UPDATE_FAILURE(ITTI_MESSAGE_GET_INSTANCE(received_msg),
//						&M3AP_ENB_CONFIGURATION_UPDATE_FAILURE(received_msg))//	break;
//
//
//       case M3AP_MME_CONFIGURATION_UPDATE:
//	LOG_W(M3AP,"MME Received M3AP_MME_CONFIGURATION_UPDATE Message\n");
//        MME_send_MME_CONFIGURATION_UPDATE(ITTI_MESSAGE_GET_INSTANCE(received_msg),
//						&M3AP_MME_CONFIGURATION_UPDATE(received_msg));
//	break;
//

//      case M3AP_HANDOVER_REQ:
//        m3ap_MME_handle_handover_req(ITTI_MESSAGE_GET_INSTANCE(received_msg),
//                                     &M3AP_HANDOVER_REQ(received_msg));
//        break;
//
//      case M3AP_HANDOVER_REQ_ACK:
//        m3ap_MME_handle_handover_req_ack(ITTI_MESSAGE_GET_INSTANCE(received_msg),
//                                         &M3AP_HANDOVER_REQ_ACK(received_msg));
//        break;
//
//      case M3AP_UE_CONTEXT_RELEASE:
//        m3ap_MME_ue_context_release(ITTI_MESSAGE_GET_INSTANCE(received_msg),
//                                                &M3AP_UE_CONTEXT_RELEASE(received_msg));
//        break;
//
      case SCTP_INIT_MSG_MULTI_CNF:
        LOG_E(M3AP,"MME Received SCTP_INIT_MSG_MULTI_CNF Message ... shoudn't be happening ... it doesn't at leaast with M2AP_MCEC\n");
        m3ap_MME_handle_sctp_init_msg_multi_cnf(ITTI_MESSAGE_GET_INSTANCE(received_msg),
                                               &received_msg->ittiMsg.sctp_init_msg_multi_cnf);
        break;

      case SCTP_NEW_ASSOCIATION_RESP:
        LOG_D(M3AP,"MME Received SCTP_NEW_ASSOCIATION_RESP Message\n");
        m3ap_MME_handle_sctp_association_resp(ITTI_MESSAGE_GET_INSTANCE(received_msg),
                                              &received_msg->ittiMsg.sctp_new_association_resp);
        break;

      case SCTP_NEW_ASSOCIATION_IND:
        LOG_D(M3AP,"MME Received SCTP_NEW_ASSOCIATION Message\n");
        m3ap_MME_handle_sctp_association_ind(ITTI_MESSAGE_GET_INSTANCE(received_msg),
                                             &received_msg->ittiMsg.sctp_new_association_ind);
        break;

      case SCTP_DATA_IND:
        LOG_D(M3AP,"MME Received SCTP_DATA_IND Message\n");
        m3ap_MME_handle_sctp_data_ind(ITTI_MESSAGE_GET_INSTANCE(received_msg),
                                      &received_msg->ittiMsg.sctp_data_ind);
        break;

      default:
        M3AP_ERROR("MME Received unhandled message: %d:%s\n",
                   ITTI_MSG_ID(received_msg), ITTI_MSG_NAME(received_msg));
        break;
    }

    result = itti_free (ITTI_MSG_ORIGIN_ID(received_msg), received_msg);
    AssertFatal (result == EXIT_SUCCESS, "Failed to free memory (%d)!\n", result);
    received_msg = NULL;
  }

  return NULL;
}

#include "common/config/config_userapi.h"

int is_m3ap_MME_enabled(void)
{
  static volatile int config_loaded = 0;
  static volatile int enabled = 0;
  static pthread_mutex_t mutex = PTHREAD_MUTEX_INITIALIZER;

  if (pthread_mutex_lock(&mutex)) goto mutex_error;

  if (config_loaded) {
    if (pthread_mutex_unlock(&mutex)) goto mutex_error;
    return enabled;
  }

  char *enable_m3 = NULL;
  paramdef_t p[] = {
   { "enable_mme_m3", "yes/no", 0, strptr:&enable_m3, defstrval:"", TYPE_STRING, 0 }
  };

  /* TODO: do it per module - we check only first MME */
  config_get(p, sizeof(p)/sizeof(paramdef_t), "MMEs.[0]");
  if (enable_m3 != NULL && strcmp(enable_m3, "yes") == 0)
    enabled = 1;

  config_loaded = 1;

  if (pthread_mutex_unlock(&mutex)) goto mutex_error;

  return enabled;

mutex_error:
  LOG_E(M3AP, "mutex error\n");
  exit(1);
}
